The present invention relates to a method of constructing brass instruments and more particularly to a method of forming the mouthpipe of a brass instrument to include a zone of increased taper which significantly improves the intonation of the entire upper octave of the instrument's normal playing range. (I.e., for purposes of this application, brass instruments comprise wind instruments having a cup mouthpiece and a cylindrical bore.)
Although the origins of brass instruments have been traced back hundreds of years to man's primitive ancestors, the basic form of the modern valved trumpet derived in the early 1800's. Since that time, consistent efforts have been made to improve the harmonic or intonation qualities of the instrument. To date, most of these improvements have focused upon the configuration of the bell portion of the trumpet.
In relation to the bell portion, it has been found that by flaring the open end of the trumpet to increase in diameter as the opened end is approached, the frequencies of the lower note resonances are shifted upward. Additionally, if the total length of the trumpet is properly adjusted for the particular bell shape, the higher note resonances will remain unchanged. Thus, with a properly shaped bell portion, the majority of note frequencies will be shifted into a form approximating a true harmonic series.
Although these improvements have proven beneficial in their general application, there exists inherent limitations in their operation which must be constantly corrected during playing by the musician. In particular, it is well known that trumpets constructed of conventional design fail to provide a chromatic scale that is nominally true to desired pitch for the entire upper octave of the instrument. (I.e., from the D natural (D.sub.5) above the 4 partial C-natural (C.sub.5) to the A natural (A.sub.5) above.) Thus, with a conventional soprano trumpet in "C", the E.sub.5 (659 Hz) note is typically flat enough to be audibly detectable in many playing situations, whereas the F.sub.5, G.sub.5 (740 Hz) G sharp.sub.5 (831 Hz) and A.sub.5 (880 Hz) notes are all very sharp. Heretofore, to intonate these upper octave notes in proper pitch, the musician would be required to conscienciously correct these normally out-of-tune notes by either extending a valve slide and/or false fingering of the trumpet valves.
Additionally, in the conventional trumpet design, the tuning slide is utilized to initially tune the instrument to desired pitch, being typically pulled outward away from the upper branch through a distance of 3/8 to 3/4 of an inch in order for the musician to play at a pitch corresponding to A=440 Hz (standard orchestration pitch). This extension of the tuning slide locally increases the bore of the instrument both in the upper and lower branch which flattens certain notes (i.e., the D sharp.sub.5 and E.sub.5) on the chromatic scale as well as produces turbulence within the instrument. This turbulence adversely affects the playability or action of the instrument which must further be constantly compensated for by the musician. Thus, there exists a need in brass instruments for a construction which corrects the chromatic scale throughout the entire upper octave of the normal playing range without adversely affecting the action and total resonance of the instrument.